BY JONATHAN LERNER

In exploding cities around the world, ever-increasing populations of the poor find themselves occupying dense makeshift settlements, or dangerously subdivided apartments, or massive, isolating housing estates. Official planning and development mechanisms seem unable to cope as cities expand in ways that are disorderly, unpredictable, and resistant to the provision of infrastructure and services. Can design solutions redress the imbalance of wealth and poverty that underlies this? Can city dwellers themselves transform dysfunctional places into communities with livable futures? Can an art museum help solve this global problem? These are questions posed by Uneven Growth: Tactical Urbanisms for Expanding Megacities, an exhibition at the Museum of Modern Art (MOMA).

Uneven Growth is the third effort in MOMA’s Issues in Contemporary Architecture series. The first was Rising Currents: Projects for New York’s Waterfront, in 2010. It elicited concepts for responding to sea-level rise and climate change two years before Hurricane Sandy’s piercing alarm, and some of those ideas have been incorporated into projects now moving toward construction in metropolitan New York. In 2012, Foreclosed: Rehousing the American Dream imagined restorative strategies for six representative American suburbs following the mortgage debacle. These concepts turned out to be more and less radical, but all were more or less doable. In the current exhibition’s catalog, Barry Bergdoll, a former head of MOMA’s Department of Architecture and Design (and still a part-time curator there), describes the series as “laboratorial,” intended to formulate and show “experimental results that do not yet exist.” In that spirit, Uneven Growth paired design firms with local knowledge together with others that have international experience on teams asked to work up speculative proposals for six cities: Lagos, Nigeria; Rio de Janeiro; Istanbul; Hong Kong; Mumbai, India; and New York. They were asked to address their city’s situations via tactical urbanism: to consider what could be effected by citizens themselves; to incorporate the cultures of improvisation that overcrowded cities naturally elicit; and to devise interventions that could be made lightly and with limited resources.

This tactical urbanist brief is a departure from the previous two undertakings in the MOMA series, in that they implicitly asked for, and resulted in, proposals that would require heavy construction, intensive capital, and the participation of planning and regulatory agencies to be realized. Tactical urbanism is also a counterintuitive choice for considering megacities, because to fundamentally and lastingly transform their conditions any solutions will have to apply at megascale.

People have been devising small, spontaneous fixes for the inadequacies of city life as long as there have been cities, but when considered as a theory of and approach to urban remediation, tactical urbanism is at least a fresh attitude. And as its adherents might point out, mainstream planning and development entities, even when they have unimpeachable intentions, are not managing the globe’s metastasizing cities particularly well.

The concept of tactical urbanism was has been heavily promoted since 2010 by Mike Lydon, a principal at the Street Plans Collaborative and a leader of NextGen, the youth brigade of the Congress for the New Urbanism. The premise is that spontaneous, cheap, bottom-up, and temporary initiatives could make tangible improvements to the urban realm at the scale of the intersection or block or neighborhood and also serve as laboratories and models for wider application. Lydon and his CNU collaborators developed an online case-study manual showcasing community-based and enterprising projects such as the unsanctioned painting of bike lanes onto city streets; “chair bombing,” wherein cast-off materials like shipping pallets are refashioned into seating for spots like bus stops; and the annual PARK(ing) Day, when on-street parking spaces are commandeered and made into temporary outdoor rooms. (There are now four downloadable editions of the manual, including one drawing on work from Latin America and another from Australia and New Zealand.) Tactical urbanism tends to treat established planning and development frameworks as obstructionist or irrelevant—or, most charitable, as sluggish and unlikely to generate nimble solutions. Its practitioners include but are hardly limited to credentialed members of the design professions; it is an inherently activist and community-based way of working on the city. Although the interventions themselves are modest and localized, their perpetrators often have a wider exhortative intent, and in some cases their actions have successfully influenced official planning at the city level. (A book on the subject, authored by Lydon and his Street Plans colleague Anthony Garcia, is due out from Island Press in March.)

Cities have “always included, if not required, incremental and self-directed action aimed toward increasing social capital, commercial opportunity, and urban livability,” acknowledge Lydon et al. But they cite three contemporary trends for why these tactics have come to be codified—and may turn out to be more potent—at this historical moment. One is the Great Recession, when funding for large-scale projects, and jobs for many who would have designed them, evaporated. This left communities without ameliorative efforts from above, and creative professionals with the time, if not much in the way of resources, to address urban conditions. The second is the reborn interest in city rather than suburban living. That’s a particularly American phenomenon and probably irrelevant to rampantly expanding cities like those MOMA selected, including New York, which is exceptional in never having been hollowed out like virtually every other city here. Anyway, to the extent that tactical urbanism as a premise is embraced internationally, the significance to it of that factor pales next to the third: the Internet, a most perfect medium for transmitting the quick, the ephemeral, and the groovy.

A megacity twofer: In Hong Kong, an informal oyster-farming settlement is next to a “new town” that has a reputation for family tragedies, attributed to its remote location, few jobs, and high density.

Now tactical urbanism has been validated by MOMA, one of the preeminent museums in the world. Since it was at the heart of the exhibition’s brief, it is one criterion for judging the proposals of the Uneven Growth teams. Another test, of particular interest to readers of this magazine, is the degree to which landscape architecture and its expertise and concerns figure in. There is, or ought to be, a good deal of natural affinity between landscape architecture and tactical urbanism. A lot of the latter’s interventions are efforts to insert or enhance public spaces or their elements—parks and gardens, circulation and wayfinding, street furniture and lighting, the rehabilitation of streetscapes and waste grounds. Many also intend to engage citizen involvement, which is of increasing importance in many landscape architecture projects. But landscape architecture as a formal and professional practice also extends to the provision of big infrastructure and to the interface between built places and natural environments at the regional scale. Tactical urbanism by definition, and as it is typically expressed, is too light and local to take those on. Which raises the question of why, in the first place, MOMA posed the challenge of salvaging cities on the verge of breakdown through the application of tactical urbanism. And the six proposals regrettably fall short by both measures.

For example, the proposal for Rio notes that, thanks to an improved economy, favela residents have increasing disposable income. To help them “reappropriate the urban environment in a more sustainable way by promoting the existing qualities of Brazilian street life,” the team RUA Arquitetos and MAS Urban Design, ETH Zurich created a catalog of ideas for low-tech products. Some would enhance private spaces, such as a reflector to light dark interiors. Others, like vessels of woven bamboo in which palm trees could be planted, or umbrellas for shade that use streetlights or telephone poles for support, would civilize the public realm. These, modest as they are, might be considered parts from a landscape architecture tool kit. And all of the product proposals are true to the spirit of tactical urbanism—ingenious, cheap, responsive to real conditions. But it’s hard to imagine these minor if useful items, even massively applied, transforming favelas as urban forms or profoundly improving life in them.

The Istanbul idea focuses not on improvised settlements but on the kind of disconnected high-rise residential wildernesses that come to surround megacities wherever the resources to erect them exist. The intent of the proposal, by Superpool and Atelier d’Architecture Autogérée, is to generate urbanity and empowerment through many small, seemingly viable, interventions such as inserting smaller structures between and surrounding the tall buildings for workshops, retail enterprises, and common spaces for tool sharing, child care, and the like. Other elements would be recognizable landscape architecture gestures: enveloping the high-rise facades with plant and food-growing superstructures—not exactly something unskilled folks can do on the cheap—and repurposing unbuilt ground for fish, vegetable, and energy farms. The underlying supposition is that altering physical space will engender alterations in social space and even household economies. Maybe so, but the mind reels at the requisite negotiation processes both among community members and between them and governmental entities; there goes the spontaneity. That aside, the extra greenery and animation of the public realm would surely make such ghastly places more livable.

The Mumbai team, URBZ and Ensamble Studio/MIT-POPlab, argues for granting the city’s vast improvised settlements legitimacy and tenure; hardly an ephemeral project itself, but assume for a minute that it could happen. Then residents could expand their houses upward using an inexpensive, ultra-lightweight modular building system. A corollary idea is a “flying carpet” superstructure system to be raised above the cramped existing urban fabric that would provide new pathways and public spaces. There’s a similar element in the Lagos proposal, by NLÉ and Zoohaus/Inteligencias Colectivas, responding to the fact that much of that city sprawls informally over tidal wetlands. It would embrace the watery environment by creating canals as transportation arteries, which would be edged by broad esplanades. Again, actually realizing such an undertaking is about as far from tactical intervention as you could get, but, assuming it came to pass, new pedestrian and public spaces would result. Aside, however, from dreamy renderings of people strolling and lounging about, which might as well have been pasted up from clip art, neither the Mumbai nor the Lagos team had anything to say about the functionality and design of these useful spaces—anything, that is, that drew on the intelligence of landscape architecture.

Lagos’s informal sprawl across tidal wetlands might be regularized with a system of canals.

The Hong Kong proposal presents a scheme for creating new islands in the harbor. That sounds good, space being so tight there and water so abundant. But these proposed islands, developed by MAP Office, are entirely conceptual, described in insultingly coy language and depicted in impenetrably abstruse diagrams. On the Island of Surplus, for example, “fragments of trash collide in an entropically generated landscape” creating a “fantastic laboratory for the manipulation of geology and geography.” The Island of Self “is made of an infinite network of pipes, wires, and gutters that serve as the main organs feeding an intoxicated population.” These islands would have been the most significant opportunity for landscape architecture in Uneven Growth, but that chance blew away in a gust of hot air.

There’s plenty wrong with this exhibition; for one not insignificant thing, its visual presentation at the museum is chaotic and frequently baffling. But most important, all six proposals disappoint in how they apply tactical urbanism—or whether they try—and they’re further weakened for failing to draw on landscape architecture. A better sense of the possible synergies between the two can be gleaned from the accompanying website to Uneven Growth,uneven-growth.moma.org, where dozens of examples of tactical urbanism from all over have been posted.

A few posts illustrate intriguing urban interventions with strong landscape architecture—or landscape design, or land art—sensibilities. It is probably no accident that the people behind these are professionals from the landscape field (or architects who obviously give landscape some attention). For the Addition by Reduction project at Carrie Furnaces, an overgrown abandoned mill in Pittsburgh that is part of the Rivers of Steel National Heritage Area, the landscape-design consultant Rick Darke is creating pathways and programmable spaces by editing the vegetation that spontaneously colonized the site. In Rome, a one-week project at another disused factory, inhabited by several hundred immigrants, created a fruit orchard in a roofless space, with the trees planted in boxes. The intervention was a project of Linaria, a nonprofit that “aims to promote the culture of the garden, the landscape, and the environment,” whose staff includes landscape architects and botanists. In a park being established on a former landfill outside Tel Aviv, students of the Spontaneous Architecture studio created a tree-form shade structure of woven branches, reminiscent of the work of the American sculptor Patrick Dougherty. For an art biennale in Shenzhen with the theme Losing the Countryside, the Taiwanese architecture collaborative WEAK! built Bug Dome, a cocoon-like structure constructed from materials found on the site. Afterward, overgrown with volunteer plants, it became a sort of semi-underground clubhouse for migrant workers in the city.

The Uneven Growth website has other examples of tactical urbanist actions that might interest, or have been improved by the participation of, landscape professionals: degraded urban spaces recycled as informal parks and plazas, inventive ways of furnishing and lighting informal public spaces, unorthodox approaches to mapping, efforts to involve community members in public design interventions. It’s a good idea to create a bulletin board for showcasing such projects, though naturally they are all too small to say much of value about the problem of megacities. This website, though, is as user unfriendly as the exhibition. Some posts are nothing more than a photograph. Many have a scrap of explanatory text, but most lack links and other identifying detail. The perpetrators, hurrying off to perform other ephemeral interventions, may perhaps be excused for neglecting to include such useful information, but the site’s designers might have thought ahead and built in a few prompts. Numerous other websites do a far better job of explicating tactical urbanism.

MOMA’s architecture curators should be applauded for their audacity and activism in focusing the museum’s considerable resources and prestige on urgent problems of our built places. In Uneven Growth, it was radical to try the tactical urbanist approach because it would by definition involve and ameliorate existing communities rather than raze them—improve conditions and household economies in the Mumbai shantytown, let’s say, rather than shoo its residents elsewhere to cobble together another one while gated-community towers for the rich go up on the site. But this MOMA project was flawed from the start because tactical urbanism isn’t so useful for taking on challenges that ultimately demand strategic intervention at the regional scale, and it never claimed it could. Beyond that, a troubling question lingers: To what extent, if any, can design affect the underlying economic injustice that creates the crisis of the megacity in the first place?

Clarifications (updated January 27, 2015): An earlier version of this review incorrectly implied that Network Architecture Lab collaborated in the scheme to design new islands in the harbor of Hong Kong. The islands were proposed by MAP Office of Hong Kong. The review also attributed the origin of the term “tactical urbanism” to Mike Lydon. In fact, Lydon attributes prior use of the term to Brian Davis.

Uneven Growth, an exhibition at the Museum of Modern Art, presented in collaboration with the MAK–Austrian Museum of Applied Arts/Contemporary Art, Vienna. On view in New York through May 10, 2015, and at the Vienna Biennale June 11–October 4, 2015.

Jonathan Lerner writes on architecture, planning, art, and design for national magazines and for professionals in those fields. Find him at www.urbanistcommunications.com.